Fluid separator and eliminator



United States Patent Charles D. Erickson Erie, Pennsylvania Appl. No. 783,203

Filed Dec. 12, 1968 Patented Oct. 27, 1970 Assignee A.0. Smith Corporation 1 Milwaukee, Wbconsin 1 a corporation of New York lnventor FLUID SEPARATOR AND ELIMINATOR l0 Clairm, 6 Drawing Figs.

US. Cl 137/202, 137/451 Int. Cl l6k 45/02, .F 161 55/06 Field ofSelrch 137/202,

451: 251(CT Digest): 137/192 IIIIIIIIIIIIIIIIII l t "0 III/II, 7

[56] References Cited UNITED STATES PATENTS 2,180,173 11/1939 Share Primary Examiner-Alan Cohan Att0rneyAndrus, Sceales, Starke and Sawall ABSTRACT: This disclosure relates to an air separator and eliminator including a self-aligning valve structure interconnected to a float mounted in an air separating chamber connected in a liquid dispensing line. The valve structure includes a pair of air outlets, one of which is connected to exhaust the art from the chamber and the other of which is connected toa shutoff valve if sudden accumulation appears in the separating chamber.

I [III FLUID SEPARATOR AND ELIMINATOR This invention relates to a fluid separator and eliminator apparatus and particularly to such apparatus having an improved float and valve release means.

In liquid petroleum dispensing systems, air elir'ninators may be employed to automatically eliminate air or other gas from the stream of flowing liquid. Thus, free air or other entrained gases which pass through the meter result in an erroneous reading of the actual volumetric flow of liquid. Under certain abnormal situations, the flow may desirably be terminated in response to a selected accumulation of a foreign substance or fluid in the flowing liquid.

Float activated valve systems have been suggested for incorporation into the flow line with a separating chamber within which the air or other similar fluid accumulates to actuate a float valve and provide the desired functioning. For example, U. S. Pat. No. 3,252,473 discloses a float operated air eliminating valve structure. A somewhat similar system is shown in US. Pat. No. 3,131,709 wherein a float valve actuates a flexible flat band which is connected to the float and caused to selectively open and close an aperature in a flat wall in response to the positioning of the float. Although prior art float activated eliminators have been satisfactorily employed, they generally require special guide systems to establish predetermined float paths for proper operation of the valve. The secondary or auxiliary confinement results in the usual additional original and maintenance costs as well as reduced reliability and life.

The present invention is particularly directed to a highly novel and improved apparatus to separate gas or other fluid from the liquid, and if desired, to actuate the pilot control system for temiinating or otherwise controlling the flow in response to a selected accumulation of the foreign fluid.

Generally, in accordance with the present invention, a selftracking valve unit which is preferably constructed in accordance with applicant's copending application entitled Positioning Apparatus And Valve" which was filed on October 8, 1968 and is assigned to the same assignee as this application, is connected to a float and forms the upper guide therefore. The lower end of the float is provided with a simple guide to generally hold the float in a vertical direction. The

' valve unit as disclosed in the copending application includes a pair of members defining curved surfaces arranged in physically opposed relationship. The valve members are interconnected by a pair of involuted opposed bands fixed at the opposite ends to the members, and in particular, being curved over the opposed curved surfaces of the valve members. Thus, the one band is connected to the first member and extends over the first curved surface and around the generallyopposite curved surface of the opposite fixed member. The second band is oppositely disposed with respect to the two members and extends therebetween and over the opposite side of the curved surface of the one member and the opposite side of the surface of the second member. Thus, relative movement between the two members is a rolling action with the opposed bands inversely engaging the peripheral surface of the two members. The one member is fixed and moves the other, the rolling contact interengagement and release virtually eliminates friction and thus requires minimal operating force. By providing selective openings in the curved surfaces in alignment with the bands, the flow between the interior and exterior of the fixed member is controlled. The opposing bands establish counter forces which virtually eliminate the input force requirements.

In a highly satisfactory air eliminator, a chamber unit was connected in the flow line and included a float chamber. The one cylinder was mounted in the valve chamber as a fixed member with the opposite ends interconnected respectively to an air exhaust and to a flow control means. The fixed cylinder had a central dividing wall with a pair of apertures correspondingly axially spaced, one each to the opposite side of the wall. The valve bands were secured respectively to the fixed cylinder in alignment with and extended over the apertures and in an involuted or inverted manner about the generally opposite portion of the adjacent second cylinder which was mounted to move as a band control. A pair of opposing or balancing bands were secured inboard of the valve bands to thefixed cylinder and to the movable cylinder and extended about the fixed and movable cylinders in the direction opposite that of the valve bands. A bracket connected the movable cylinder to the upper end of a float in the float chamber. The lower end of the float was guided by a rod and opening guide arrangement to permit the float to move freely between the upper attachment to the free and selftracking cylinder and the lower guide means.

The present invention thus provides a highly inproved flow. assembly which provides a highly reliable sealing means with a rapid response to accumulation of air and the like. The guide means is extremely simple and reliable and thus may provide a relatively long life with minimum service requirements.

The drawings furnished herewith illustrate the .best mode presently contemplated by the inventor for carrying out the present invention, and clearly disclose the above advantages and features as well as other which will be readily understood from the following description.

In the drawings:

FIG. 1 is a side elevational view of a separating device connected in a metering flow line for a petroleum product or the like;

FIG. 2 is an enlarged side elevational view of the Separator constructed in accordance with the present invention with parts broken away to show internal details of construction;

FIG. 3 is a vertical section taken generally on line 3-3 of the separator shown in FIG. 2;

FIG. 4 is a fragmentary horizontal section taken generally on line 4-4 of FIG. 2.

FIG. 5 is a vertical section taken generally on line 5-5 of FIG. 4 with the valve in a closed position established by the raising of a valve assembly control float; and

FIG. 6 is a plan view of the valve assembly shown in FIGS. 25.

Referring to the drawing and particularly to FIGS. 1 and 2, the present invention is shown as a liquid flow system including a flow line 1 incorporating a meter 2 to record the volumetric flow of liquid, such as fuel oil, through the line. An air gas eliminator 3 is interconnected upstream of the meter, and is adapted to remove free air or other entrained gases which may be present in the flowing liquid before its entry into the meter. In the illustrated embodiment of the invention, the gas separator or air eliminator 3 is interconnected to actuate a pilot valve 4 and control the flow through line 1 and to a suitable air vent 5 to remove the entrained air or other gases.

As most clearly shown in FIGS. 2 and 3, the gas separator generally includes an outer flow casing or housing 6 having a lower outlet portion 7 and a laterally extending inlet portion8 immediately above the outlet portion 7. A tubular filter screen 9 is secured in the laterally extending inlet portion. The screen is a strainer and difl'user which serves to remove foreign material from the liquid and to further diffuse the liquid stream in accordance with known practice. A float chamber 10 is disposed immediately adjacent the inlet chamber and thus in communication with the inlet and outlet chamber. A float 11 is disposed within the float chamber 10 and interconnected to a valve assembly 12 located immediately above the float 11. A valve head 13 is secured to the housing 6 immediately above the float chamber 10 and defines an extension of chamber 10 to enclose the valve assembly 12. The head 13 includes oppositely disposed outlets connected respectively to the pilot valve 4 via a conduit 14 and the air vent 5.

The liquid in the float chamber 10 will normally support the float 11' in a raised position corresponding to a closure of the valve assembly 12, as more fully developed hereinafter. Air or other gas which may be entrained within the liquid is released,

with the casing 6 and accumulates within the upper end of the float chamber 10 and causes the float 11 to drop or lower in 1 Y ration in the absence of any restraint.

den aecumulation of titer other et; the exhaust through vent More particularlyin the floatxchamber, to the'positionof 2-4. tend in an opening of the valve assembly 12 and exhaustsairto air vent 5 and to the pilot valve 4. lfthereis an unusual or sude,

the band 24 has iteohe eddseeutedet ixed to the upper end I ofthe'fixed cylinder l8as by set 31generally diametri .callyoppositefromtheattaclunent ofjthe band22by aset the illustratedembodiment of theinvention, float 11 is a sealed bulb-typemember within chamber 10.

' thefloat chamber 10. A guide rod 15 is secured to the under-. side of the float 11 and extendsdownwardly through an open;

ing 15a in guidewall 16 which is formed in the lower portion w of the float chamber. Theopening 15a is slightlylarger than rod 15 to allow essentially free and unrestricted vertical movet mentofthefioat11. 1 t g I A j generally rectangular; valve attachment "bracket. 17 is secured to the upper'end of the float lltwith the side arms of the bracket 17 extendingupwardlyinto the valve assembly Q head 13 and connected to position thevalve assembly .12. The valveasembly. 12 is shown in FIGS. 1-1-6 in a preferred constructionin' accordance with the previously identified copending application of this applicant for a gas separator for. 1. in petroleum flow line. or the like. Generally-theassemblyint eludes a fixed valvecylinder 18 extending laterally of the head: 1 13 anda spaced parallel control cylinder 19 interconnected by t a plurality of bands to cylinder1 8. Cylinder 19'is .intercon-t nect'editoithe bracket 17 for positioning relative to float 11 in accordance with. relative levels: of the gas and liquid in r p cylinder is is provided with'a pair of axially y spaced and similarcircumferentially extending "valve openings;

or apertures 20 and21. Cylinder 19 is interconnected tothe:

1 The bands 22 and23 are similarly secured to face of the float activated cylinder 19.

Theacylinder 19 is provided with bands 22 and 23. 'lhe'balancing bands 24 and 2,5.are similarlyi secured to thecylinders in fixed relationship thereto. Thus,

thecylinders 18 and 19 in a generally invertedor involuted manner. Thus; 1 referring particularly :to band 22 and FIGS. 2and 5, the one i end of band 22 is fixed to the bottom side or. surface of the 11, fixed cylinder asbya set screw 26. band 22 is aligncd with the aperture 20 and extends over .the curved surfaceincluding the aperture 20 and then outwardly overand around the sure t fixed valve cylinder 18 by a pair'of valve'bands 22 and23 lwhich'are aligned with the apertures or valve openings 20 and j 21 respectively/[hevalve bands22and 23 areadapted to progressively engage :and disengagethe fixed cylinder 18 to correspondingly 1open and close .the aligned apertures or 1 valves20 and 21. A pair of bias or balancing bands 24 and 251 are secured in an inverse or opposite manner to the cylinders 18 19 to provide; an automatic guided movement ofthe two cylinders withthef valve bands inrolling engagement with.

respect to the adjacent curvedsurfaces of the cylinders. y

p More particularly, the sealingbands;22.and'23 and the- .balaneing 25 are resilient, flexible'strips which x maybe formed of a suitable spring metal, a rubber-like materialt having stiffening members or] the like; The bands are preferably such that they will tend to a planar-configm a circumferential opening I t I 27 and a coil spring 28 having hook'ends 29 and 30 hookedfto theadjacent end of the 22 and to the cylinder'at the t remote end of the opening 27to resiliently tension theband 22 about the cylinder118. The float activated cylinder l9is of a slightly lesser width than the fixed cylinder .18 but extends outwardlyjbeyondthe axial position of the apertures 20 and x severaltflexible bands,'therefore,;intending to assume their normal position, determine theposition of the e ihdett aah is withrespecttoeachother. sign holds rnovable cylinderr 19 adjacent cylinder. s and thereby definesta telrte htaihed and selfvalv'etmechanism. float-(l1 is' and maybe cont netted directlyto cylinder19 which fomisthe only r 'and 25 similarly pambetween the cylinders 18an'd 19in the direction. oppositethatwofbands 22 are fixed @screw 26. The band extends :over the. topv surface of the cylinder 18 in the direction of the valveflopenings'20 21 I downwardly .the'float activat ed cylinders 18 and. ne o e gehder the band'24 t curves over theadjacent cylinder 19 and issecuredtothecylinderbyasetscrew 32tilhus thebandsz4 required connection and guide forIthe-movable portion ofthe 1 valve upperend of floatlinventionthereby I eliminates thesrequirement forfiauxiliary structures such as frames, -eonstn'etors; retainers and the;

similar secondaryconfinementmearmwhich have previously I ;,generally been employed'in float activated; valve assemblies andthe like. j i

Theopposite ends ofthe movable cylinder. aretclosedby I apertured end walls 33 and 34 ha'vingacentral bearing pins or. i

shafts sst hie project outwardly and into the side arms of the encircling supporting bracket 17. fioatfactivated cylinder l9'issecured to the bracket by suitablewsnap rings 36which snap suitable recessesin the outer nds ofithe bearing pins or.

coupling {portion 41 extending inwardly therefrom-into a nected to the opposite ends ofthe fixed cylinder 18 to provide intercommunication between the adjacent. portion of the cylinderand the air vent 5 andthe poppet-valve 4, respective- 1y f rhe fixed cylinder 18'is providedewith in integral central rnostclearly shown in FlG."5, the fixedcylinder 18 is y p aligned with a pair of outlet hubs 38' to the opposite side sof the housing andinterconnected thereto by similar otiti letc ouple'rs 39 which are boltedor secured to hubs and project inwardly into the cylinders. The coupler 39is I provided with an outlet aperture orope ningfig communicating directlywiththe-adjacent portion of cylinder 18 with a I recessed portionof the adjacent end offixed cylinder 18. At f rst, O -ring seal 421s between the hub 37 a'ndfthe adjacent of theoutlet couples: A second innerO- ring seal:43 is disposed between the innerzprojection or portion1 4l of the coupler 39 interior. surface of the cylinder 18. In this manner, couplers 39 are intercon- 1 wall 44 having a central openin'g which issealed by a pipeplug I 45. The sealed central wall 44 defines a pairof separate signal chambers aligned respectively with-the; valve openings. or

apertures22and2l toprovideseparate signals'totheairvent *sahdvavee a The mete of the fixed cylinder 1a isprovided with a scalingicover fli in the form of asheet-likelniember which is secured to the exterior surface of ihOiCYIlDdCI. The

member or cover 46 maybe a resilient rubber-like material "which is'provided with suitable slots 47 aligned with the apertures 2o arid 2110f t e 'e hhdetis. sealing member 46 is cylinder and open-towards each the'cri'rnped ends of the .rnember bent .backwardly into U shaped .com ecting plates. Suitable eoil springsksolintereonnect the Plates 48 andt49iatlaterally locations to rear 1 ml of a width. slightly less than the length of thecylinde r l8 and 3 the opposite longitudinal ends are clamped within generally I U-shaped places 49 i'espectively; The con- 7 21,8 most clearly-shown in FIGSLZ 5, to permit at-] inecting plates 48 and 49 the back .of the t tachment of .the'bands 22'and 23 to the outer portions thereof. a

y j Theband 231is secured tocylinders l8-and19in the same manner. as. band 122.. Theibalancingj ba'nds 24 and 25 are I disposed in'laterally spacedrelations hip between the valve the presence of foreign matter. The thickness of the sealing member 46 is preferably held to a minimum such that the valve seat is not excessively raised with a corresponding change in the curcature of the sealing bands.

The spring loaded tension of the bands 22 and 23 imparts an initial loading on the valve seats to assure a highly efiective, liquid tight seal with zero pressure differential across the unit. Further, as the outer external pressure applied to the cylinder 18 increases, the sealing effectiveness increases.

in the operation of the illustrated gas separator, the liquid flow passes through the casing 6 between the inlet and outlet portions 8 and 7. The float 11 is normally in a raised or upper position with the valve activated cylinder 19 in a corresponding raised position, as shown in FIG. 5. In this position, the valve bands 22 and 23 are tightly clamped against the cylinders l8 and over the apertures 20 and 21 in the fixed cylinder to positively seal the valve openings. The float 11 in moving the cylinder 19 upwardly causes the sealing bands 22 and 23 to essentially freely roll over the sealing surface to affect the desired closure of the valve openings. The curved sealing bands permit them to resist a greater internal pressure for any given band thickness when compared with a relatively planar or flat type band seal. The reverse interconnection of the sealing bands 22 and 23 and the balancing bands 24 and 25 maintain the illustrated fixed relation and positively insure the rolling interengagement of the sealing bands with the fixed cylinder and the release of the balancing bands with respect to the fixed and movable cylinders.

If a charge of air or a liquid-air mixture enters into the gas separator housing 6, the air rapidly rises into the higher portion of the float chamber and displaces the liquid around the float 11. As the liquid level drops, it approaches the bouyancy limit level of the float 11 and at a selected level determined by the construction of the float causes the float to move downwardly with the liquid level. This results in a lowering of the float activated cylinder 19 with a rotation of the cylinder 19 accompanied by progressive release of the sealing bands 22 and 23 from the fixed cylinder 18 and a corresponding intersurface engagement of the balancing bands 24 and 25 with the surface of the cylinder 18. Simultaneously, bands 22 and 23 engage cylinder 19 and disengage cylinder 18, to establish the condition shown in FIGS. 4 and 5. As a result, the valve openings or apertures 20 and 21 are opened and the accumulated air or other gas passes through the respective chambers of cylinder 13 to the air vent 5 and the pilot valve 4 to permit release of the accumulated air and to simultaneously provide a signal to the pilot valve 4. If there is sudden accumulation, the float 11 drops rapidly and the signal to pilot valve 14 terminates flow until a selected amount of the air escapes through vent 5.

As previously noted, the opposite or involuted bands interconnecting a pair of members having the curved surfaces establishes a self-contained and self-tracking valve assembly. Consequently, the operation of the gas separator does not depend on a preselected traveling of the float on a predescribed path. The float 11 is therefore allowed to travel freely between the upper attachment of the cylinder and the lower guide provided by the shaft guide 15.

Generally, the movable cylinder 19 will roll freely and es-. sentially frictionless because the energy released by unbending of the one set of bands is equal to the energy required to bend the opposite set of bands. As a result, the combination float and free moving valve member establish a rapid response with a direct acting pressure signal applied to the control valve which may be of any suitable construction which provides the desired response to the pressure signal.

The valve may be readily biased with a constant forceto operate in either direction by changing the relative spring dimensions or spring characteristics of the band members. Such bias may be desirable in order to decrease the float operating load and response time to allow the valve-to open more freely against pressure and the like.

Generally, the band material is to be selected in accordance with the life and duty cycle requirements. The band material may be subjected to a corrosive action as the result of moisture condensationshould have a normally long life in excessive of 10 years. An l8-chrome, 8-nickel alloy steel has been found to be suitable for a petroleum product system.

I claim:

1. In a fluid separator apparatus comprising:

a housing defining a float chamber and a valve chamber extending therefrom;

a valve assembly having a pair of valve members having cylindrical surfaces, a first band means having means to resiliently urge the band to a preselected configuration and passing between said members and'bent over said cylindrical surfaces and connected at spaced portions to said members, a second band means having means to resiliently urge the second band means to a preselected configuration and passing between said members in the opposite direction from said first band means and bent over said cylindrical surfaces and connected at spaced portion to said valve members, said first and second band means constituting the sole supporting connection between said members and being selected to maintain the members in predetermined spaced relation with the band means in surface engagement with the cylindrical surfaces, a first of said valve members having a valve opening in the cylindrical surface aligned with the band. means;

means to fixedly mount said first valve member within said valve chamber with said second valve member being free to. move about the first valve member in accordance with the inverse engagement and disengagement of said first and second band means; and

a float member disposed within said float chamber, means to connect the upper end of thefloat member to said movable valve member, said second valve member constituting the guide means for said float member.

2. The fluid separator apparatus of claim 1 including a flow control means responsive to a fluid signal and wherein said first valve member includes a pair of valve openings aligned with said band means and having separate internal chambers aligned with each valve opening, means to connect one internal chamber to the atmosphere and the second internal chamber to said flow control means.

3. The fluid separator of claim 1 wherein the valve chamber extends upwardly from the float chamber and said float member includes a depending bottom guide member, and said housing includes a wall means having an opening through which said guide member freely moves.

4. The positioning apparatus of claim 1 wherein said members are cylinders;

said first band means including a flat strip of resilient metal;

and

saidsecond band means including a flat strip of resilient metal.

5. The fluid separator of claim 1. wherein the valve chamber extends upwardly from the float chamber and said float memberand housing include a lower guide means for guiding the lower end of the float member.

6. The fluid separator of claim 1 wherein the valve chamber extends upwardly from the float chamber, said housing including a flow passageway extending laterally. from one side of the float chamber and having an upper inlet means and a bottom outlet means, said float member constituting a sealed hollow ball member aligned with and disposed below said second valve member, and means connecting the top of said ball member to said valve member.

7. The fluid separator of claim 1 wherein the valve chamber extends upwardly from the float chamber, said housing including a flow passageway extending laterally from one side of the float chamber and having an upper inlet means and a bottom outlet means, said float member constituting a sealed hollow ball member aligned with and disposed below said second valve member, and said second valve member being a cylindrical memberhaving a axis, and a bracket means f' connected to the ball member and to the opposite endsof the 3 cylindrical member.

the bracket means to the cylindricalfmember constitutes wherein connection of rotatable connectionsat the of said cylindrical member.

9:lhe fluid separator of claim 1 wherein the valve chamber extends tupwardlyrfrom the float chamber, said first 'valve member being a cylinder extending between and sealed at the opposite ends to the walls of said valve chamber,lcy linder l0. 'l he fluid separator of claim 9 having 1 a flow control meansresponsive to a fluid signal connected to one of said connecting means, the other of said; connecting means being I connected to a vent means. 

